1. Field of the Invention
The present invention relates to a workpiece support apparatus and, in particular, to an apparatus which positions the workpiece and provides support while allowing access to both sides of the workpiece.
2. Description of Related Art
Electronic packages such as multilayer ceramic packages can be manufactured using unfired ceramic greensheets which are nominally 0.2 mm or 0.28 mm thick. Typical greensheets which are 185 mm or 215 mm wide are worked to make up to nine parts or electronic packages per sheet.
It is desirable to use larger workpieces, for example, 450 mm wide greensheets could be used to make up to 81 electronic packages per sheet. However, larger greensheets are subject to sagging and stretching which makes them difficult to handle and work. Tooling such as cutting, punching, laser cutting, drilling or the like requires appropriate support. Present methods do not facilitate the working of large workpieces because they do not provide the appropriate support for the workpiece which could cause inaccurate patterning.
Further, conventional methods limit access to at least one side of the workpiece, i.e. the bottom side, and provide a limited active area. The active area of the workpiece is the area subject to the tooling. For example, a 450 mm wide greensheet can have an active area 418 mm wide. Access to all sides of the active area is preferred. For instance, access to the bottom side of a workpiece would allow the positioning of tooling, such as a vacuum plenum, underneath the workpiece and access to the largest possible area would alleviate the problem of void areas which cannot be worked.
Bearing in mind the problems and deficiencies of the prior art, it is therefore an object of the present invention to provide a workpiece support apparatus for supporting a workpiece whereby access to an entire active area is possible.
It is another object of the present invention to provide a workpiece support apparatus for supporting a workpiece whereby access to top and bottom workpiece areas is provided.
A further object of the invention is to provide a workpiece support apparatus for supporting a workpiece which minimizes sagging and stretching of the workpiece, particularly at the point of the machining operation.
It is yet another object of the present invention to provide a workpiece support apparatus for supporting large flexible workpieces.
It is yet another object of the present invention to provide a workpiece support apparatus which may be used for positioning the workpiece.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.